Global Patent Index - EP 0405074 A3

EP 0405074 A3 19910703 - PACKET DATA COMMUNICATION SYSTEM

Title (en)

PACKET DATA COMMUNICATION SYSTEM

Publication

EP 0405074 A3 19910703 (EN)

Application

EP 90106789 A 19900409

Priority

US 37445289 A 19890629

Abstract (en)

[origin: EP0405074A2] A packet data transmission system is used to link a number of remote hand-held data-gathering units (15) such as bar code readers to a central computer (10) which maintains a database management system. Data packets are sent from the remote units by an RF link to intermediate base stations (12, 13, 14), then sent by the base stations to the central computer (10) by a serial link. Direct sequence spread spectrum modulation is used for the RF link. The remote hand-held units initiate an exchange using RF transmission to and from the base stations (12, 13, 14), receiving only during a rigid time window following a transmission from the remote unit. The base stations (12, 13, 14) cannot initiate communication to the remote units, but instead send data to the remote units only as part of the exchange.

IPC 1-7

G06F 13/42; H04J 3/24

IPC 8 full level

G06F 17/40 (2006.01); G06K 7/00 (2006.01); G06K 7/10 (2006.01); G06K 17/00 (2006.01); H04B 1/707 (2011.01); H04B 7/24 (2006.01); H04J 13/00 (2006.01); H04L 1/16 (2006.01); H04L 5/14 (2006.01); H04L 12/28 (2006.01)

CPC (source: EP US)

G06K 7/0008 (2013.01 - EP US); G06K 7/10356 (2013.01 - EP US); G06K 17/0022 (2013.01 - EP US); H04B 1/707 (2013.01 - EP US); H04L 5/1484 (2013.01 - EP US); Y02A 90/10 (2017.12 - EP US)

Citation (search report)

Designated contracting state (EPC)

DE FR GB IT

DOCDB simple family (publication)

EP 0405074 A2 19910102; EP 0405074 A3 19910703; EP 0405074 B1 19970618; AU 5808090 A 19910103; AU 627333 B2 19920820; CA 1310370 C 19921117; DE 69030936 D1 19970724; DE 69030936 T2 19980129; DE 69034229 D1 20060824; DE 69034229 T2 20070531; EP 0770962 A2 19970502; EP 0770962 A3 19970702; EP 0770962 B1 20060712; JP 2506481 B2 19960612; JP H0338133 A 19910219; US 5029183 A 19910702

DOCDB simple family (application)

EP 90106789 A 19900409; AU 5808090 A 19900629; CA 614732 A 19890929; DE 69030936 T 19900409; DE 69034229 T 19900409; EP 96118994 A 19900409; JP 11669790 A 19900502; US 37445289 A 19890629